Pulmonary emphysema is a disease featured by the irreversible progression after occurrence. So it is an important technology that can provide image diagnosing information which allows an early detection of pulmonary emphysema and an assessment of progression of the pulmonary emphysema, to doctors.
Actually, an image diagnosing technology for assessing a progression of pulmonary emphysema includes: extracting a lung field region and a pulmonary emphysema region from a tomographic image having the entire lung field region based on thresholds; calculating a ratio of the pulmonary emphysema region to the entire lung field region; and displaying the outer contour of the pulmonary emphysema region in different colors depending on the value of the ratio so that the progression of pulmonary emphysema can be intuitively understood (for example, see Japanese Patent Application Laid-Open No. 2003-10171).
Patent Document: Japanese Patent Application Laid-Open No. 2003-10171
However, in the extraction method disclosed in the Japanese Patent Application Laid-Open No. 2003-10171, there is a possibility of an excess extraction since extra several pixels are extracted to be added to the original size of a pulmonary emphysema region. That is, the Japanese Patent Application Laid-Open No. 2003-10171 was made without consideration for enhancing accuracy in extracting a pulmonary emphysema region.
In an aspect of this disclosure, there is provided a medical image diagnosing support method and apparatus, and an image processing program which can achieve improved accuracy in extracting a pulmonary emphysema region.
In another aspect of this disclosure, there is provided a medical image diagnosing support method that includes: a site region extracting step for obtaining a tomographic image which is picked up by a medical image diagnosing apparatus and extracting a predetermined site region from the obtained tomographic image; a first region extracting step for extracting a first lesion candidate region from the site region based on pixel values of the site region extracted in the predetermined site region extracting step; a second region extracting step for extracting a second lesion candidate region from the site region based on a distribution of the pixel values of the site region extracted in the predetermined site region extracting step; and a region correcting step for correcting the first lesion candidate region extracted in the first region extracting step by using the second lesion candidate region extracted in the second region extracting step.
The predetermined site is preferably the lung, and the lesion candidate is preferably the pulmonary emphysema herein. However, since the site may be lumen organs such as the enteric canal, and the lesion candidate may be applied to detect cancer cells, the term “predetermined site” and the term “lesion candidate” are used herein.
In another aspect, there is provided a medical image diagnosing support apparatus that includes: a site region extracting device which obtains a tomographic image which is picked up by a medical image diagnosing apparatus and extracts a predetermined site region from the obtained tomographic image; a first region extracting device which extracts a first lesion candidate region from the site region based on pixel values of the site region extracted by the predetermined site region extracting device; a second region extracting device which extracts a second lesion candidate region from the site region based on a distribution of the pixel values of the site region extracted by the predetermined site region extracting device; and a region correcting device which corrects the first lesion candidate region extracted by the first region extracting device by using the second lesion candidate region extracted by the second region extracting device.
In another aspect, there is provided an image processing program that enables a computer to execute: a reading step for reading a tomographic image picked up by a medical image diagnosing apparatus; a site region extracting step for extracting a predetermined site region from the obtained tomographic image; a first region extracting step for extracting a first lesion candidate region from the site region based on pixel values of the site region extracted in the predetermined site region extracting step; a second region extracting step for extracting a second lesion candidate region from the site region based on a distribution of the pixel values of the site region extracted in the predetermined site region extracting step; a region correcting step for correcting the first lesion candidate region extracted in the first region extracting step by using the second lesion candidate region extracted in the second region extracting step; and a displaying step for displaying the first lesion candidate region.
Thus, the accuracy in extracting a lesion candidate region can be improved.